Linux进程间管道通讯，两个子进程间的通讯

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>

int main(void)
{
    int n;
    int status;
    pid_t pid_1, pid_2;
    int fd[2];
    char buffer[100] = "main function!";
    
    if(pipe(fd) < 0)
    {
        perror("pipe failed!");
        exit(1);
    }
    
    if((pid_1 = fork()) < 0)
    {
        perror("fork 1 failed!");
        exit(1);
    }
    else if(pid_1 == 0)
    {
        strcpy(buffer, "info from process 1\n");
        //printf("%d\n", strlen(buffer));
        close(fd[0]);
        write(fd[1], buffer, strlen(buffer));
        exit(0);
    }
    if((pid_2 = fork()) < 0)
    {
        perror("fork 2 failed!");
        exit(1);
    }
    else if(pid_2 == 0)
    {
        close(fd[1]);
        n = read(fd[0], buffer, 100);
        printf("%s", buffer);
        exit(0);
    }
    
    waitpid(pid_1, &status, 0);
    waitpid(pid_2, &status, 0);
    
    printf("%s\n", buffer);
    
    return 0;
}

父进程分出的两个子进程之间能够经过pipe管道通讯。父进程和子进程也能够经过pipe管道通讯。

可是要注意的是在父进程中定义的buffer数组在父进程分出子进程的时候会为两个子进程各自clone一份，因此在子进程中对buffer的操做不会影响父进程和另外子进程中的buffer